Recommended: Bird Sense

Birds are more like humans than many realize: they are bipedal, they rely primarily on sight and hearing, and most are monogamous. Birkhead, a professor at the University of Sheffield in England, has spent his career studying bird behavior and fills his book with evocative stories and observations about numerous species, including flamingos, parrots and his beloved long-tailed sylph hum­mingbird. Each chapter is devoted to a particular sense or trait—“Touch,” “Hearing,” “Seeing”—with “Emotions” being one of the most nuanced. Birds perform increasingly elaborate greeting rituals the longer they have been away from their partner, he writes. Does that mean they ex­per­i­ence feelings the same way humans do? Birkhead is reluctant to draw a con­clu­sion, letting the observations speak for themselves.

This English translation of a European best seller lays out German economist Sinn’s controversial ideas about how to reduce carbon emissions. European and American politicians, he argues, are too focused on reducing fossil-fuel demand and not focused enough on curbing supply. As a solution, he proposes a “Super-­Kyoto” scheme in which consumer countries would form a cap-and-trade system that would limit each government’s fossil-fuel purchases—similar to the way ration cards worked during World War II. In addition, the cartel would levy source taxes on producers’ capital income, encouraging them to leave more of their resources underground.

University of Oxford geneticist Sykes sets off on a three-month journey across the U.S., accompanied for a time by his teenage son, who is about to go off to college, collecting spit from volunteers along the way. The result is a beautifully written travelogue and valuable genetics primer that paints an intriguing, anthropological history of the country. Some of Sykes’s (not always surprising) results suggest that racial intermixing appears least common in New England, that nearly all Americans whose ancestors arrived as slaves from Africa have European DNA, and that European genes began mixing with those of Native Americans some 10,000 years ago, hinting at a possible European origin for some Native Americans.

Kemp has hit on a fascinating yet almost entirely unknown subject: ambergris, a rare by-product of sperm whale digestion that is worth nearly as much as gold. Its value comes primarily from its scarcity: an estimated 1 percent of sperm whales produce it, and circumstances have to be just right for it to wash up on shore. Whereas ambergris is usually fatal to the whales that produce it (it can rupture their intestines, as described in one grim passage), it has been prized by perfume houses for its stabilizing effect and “ani­malic” scent and by collectors who use it as an aphro­disiac. Kemp’s perseverance in unraveling this story is admirable, although the book’s pacing is uneven.